Wait until all entries are made for the month. The January reports can't be printed until all the bills - phone bill, credit cards, etc. - are received (or accrued). This is usually sometime toward the end of February.
Before printing all the monthly reports, run the first two - To Do List [Recurring Transactions] and Trial Balance - and study them thoroughly. It's depressing to run a clean set of monthly financials and then discover that your monthly depreciation entry was overlooked.
Here are the reports you should run after entries have been made for the month:
At the end of every month you may want to take some time to analyze the performance of your business. Two very helpful reports for this are: